What beachgoers need to know about fecal contamination

Stay out of the water and off of the sand.
(AP Photo/Herald-Times Reporter, Matthew Apgar)

If your response to learning the local beach is closed due to fecal contamination is to wrinkle your nose and lay out your blanket for sunbathing on the sand, you may want to reconsider.

A press release on a new study, published in the journal Environmental Science & Technology, notes that scientists have for a decade known what many beachgoers don't: that the fecal bacteria that lurks in sand can be as much as 100 times higher than what's in the adjacent seawater.

Researchers at the University of Hawaii at Manoa set out to investigate why. To do so, they conducted "laboratory microcosm experiments" involving beach sand, seawater, and sewage.

They found that "common fecal indicator bacteria ... showed significantly smaller decay rates in beach sand than in seawater," essentially confirming the prior research. How does the fecal bacteria get there? A Lake Superior beach monitoring group explains it can be tough to pinpoint exact sources "because of the complex workings of wind, weather, and water patterns." The bacteria originates with "warm-blooded animals" (think everything from humans to sea gulls to deer) and can get to waterways via storm runoff, leaking sewers, improperly discarded diapers, or even from swimmers who have accidents.

The press release notes the bacteria can cause stomach aches and diarrhea. (Pools have their own problems: urine.)